The rock on sign upside down. Given as a rude gesture to mostly people wearing Slipknot shirts, and shirts of other gay Metal bands. It is basically saying the opposite of "Rock on".
I saw this kid at the mall in a Slipknot shirt, and I gave him the upside down rock on sign. Then he ran away and cried.
A dance one does when Rockefeller Street comes on where both arms go in a diagonal direction upwards, then on the other side, back to the other side but do it twice, then back to the other side, and repeat. This dance originated from 2 kids doing this dance to this song.